This project continues studies of how lipooligosaccharide (LOS) mimicry of human glycosphingolipids (GSL) enables the transmission of Neisseria gonorrhoeae in order to find ways to prevent it. LOS are outer membrane glycolipids that have a glycose moiety that consists of proximal Basal Region and three short distal chains, termed alpha beta and gamma. Many alpha chain oligosaccharides are structurally identical to those of lacto- (Lac-R), globo- (Pk (Gb3) and P1), paraglobo- (lacto-N- neotetraose (LNnT)), and gangliosyl (Ga1NAcbeta1 yields 3LNnT) series GSL. LOS are involved in attachment to and invasion of epithelial cells and in evasion of immune clearance mechanisms. Gonococci shed during gonorrhoea make larger LOS. The higher Mr LOS made by MS11mkC - a strain used in human experimentation -have polylactosamine structures. Polylactosaminylation explains the higher Mr molecules of this variant, but not those of others. Some serum resistant (serr) gonococcal strains extend the LOS beta chain to form an alpha-lactose that is parallel to the beta-lactose of the alpha chain, and meningococci can extend the gamma chain. We will structure higher Mr LOS made by clinical isolates; LOS made by serr strains, and LOS that appear to have higher order (Gb4 and P1) globosyl oligosaccharides that are isobaric (same Mr) with paraglobosyl and gangliosyl LOS, respectively. We particularly want to know whether higher Mr LOS have parallel GSL-like antennae that could cross-link epithelial cell receptors. We will continue to rely on mass spectrometric techniques. We know little about gonococcal LOS lipoidal moieties. This information is needed because the lipoidal moiety influences the conformation of the glycose moiety in ways that affects the latter's ability to bind glycoproteins, including antibodies. Available structural information from degraded LOS leaves known O-acyl lipoidal moiety heterogeneity unexplored. We will develop methods that allow us to structure intact LOS without prior degradation. MAbs have been used extensively in studies of gonococcal pathogenesis as surrogates for glycose structures; however, we do not have mAbs that discriminate among known glycose structures, much less for those that have yet to be found. We want to expand our library of mAbs to include additional specificities. These mAbs will be necessary for complete studies of the role of LOS in pathogenesis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI021620-16
Application #
6362282
Study Section
Special Emphasis Panel (ZRG5-BM-1 (03))
Program Officer
Quackenbush, Robert L
Project Start
1984-03-01
Project End
2004-02-29
Budget Start
2001-03-01
Budget End
2002-02-28
Support Year
16
Fiscal Year
2001
Total Cost
$263,518
Indirect Cost
Name
Northern California Institute Research & Education
Department
Type
DUNS #
City
San Francisco
State
CA
Country
United States
Zip Code
94121
Brotman, R M; Melendez, J H; Ghanem, K G (2011) A case control study of anovaginal distance and bacterial vaginosis. Int J STD AIDS 22:231-3
O'Connor, Ellen T; Zhou, Hui; Bullock, Kevin et al. (2009) Structural characterization of an oligosaccharide made by Neisseria sicca. J Bacteriol 191:3311-20
O'Connor, Ellen T; Swanson, Karen V; Cheng, Hui et al. (2008) Structural requirements for monoclonal antibody 2-1-L8 recognition of neisserial lipooligosaccharides. Hybridoma (Larchmt) 27:71-9
O'Connor, Ellen T; Piekarowicz, Andrzej; Swanson, Karen V et al. (2006) Biochemical analysis of Lpt3, a protein responsible for phosphoethanolamine addition to lipooligosaccharide of pathogenic Neisseria. J Bacteriol 188:1039-48
Swanson, Karen V; Griffiss, J McLeod (2006) Separation and identification of neisserial lipooligosaccharide oligosaccharides using high-performance anion-exchange chromatography with pulsed amperometric detection. Carbohydr Res 341:388-96
John, Constance M; Jarvis, Gary A; Swanson, Karen V et al. (2002) Galectin-3 binds lactosaminylated lipooligosaccharides from Neisseria gonorrhoeae and is selectively expressed by mucosal epithelial cells that are infected. Cell Microbiol 4:649-62
McLeod Griffiss, J; Brandt, B L; Saunders, N B et al. (2000) Structural relationships and sialylation among meningococcal L1, L8, and L3,7 lipooligosaccharide serotypes. J Biol Chem 275:9716-24
John, C M; Schneider, H; Griffiss, J M (1999) Neisseria gonorrhoeae that infect men have lipooligosaccharides with terminal N-acetyllactosamine repeats. J Biol Chem 274:1017-25
Griffiss, J M; Lammel, C J; Wang, J et al. (1999) Neisseria gonorrhoeae coordinately uses Pili and Opa to activate HEC-1-B cell microvilli, which causes engulfment of the gonococci. Infect Immun 67:3469-80
Crooke, H; Griffiss, J M; John, C M et al. (1998) Characterization of a sialyltransferase-deficient mutant of Neisseria gonorrhoeae strain F62: instability of transposon Tn1545 delta3 in gonococci and evidence that multiple genetic loci are essential for lipooligosaccharide sialylation. Microb Pathog 25:237-52

Showing the most recent 10 out of 44 publications